Normal Trigger Intelligence

Triggers behave diversely at different times depending on the level at which they are defined. This section presents some points favoring trigger intelligence. It also highlights some examples illustrating how trigger behavior is sometimes abnormal.

How Triggers Exhibit Intelligence

The following points show examples favoring trigger intelligence:

  • While choosing from the trigger list of an object, Forms 5.0 is intelligent enough to provide triggers applicable to that object and at levels higher than the default level. Even the standard drag and drop operation is intelligent enough to recognize the appropriateness of a given trigger.
  • Inapplicable triggers defined at a particular level are not fired at runtime. For example, a POST-QUERY trigger defined at item level is not fired.
  • The behavior of a trigger is intelligent enough to decide whether that trigger should fire or not. If Fire-In-Enter-Query-Mode is set to Yes, a WHEN-VALIDATE-ITEM trigger still doesn't fire for a base-table as well as a non base-table item in Enter-Query Mode. This shows that Forms 5.0 recognizes that a WHEN-VALIDATE-ITEM is meant for validation purposes and has no purpose in firing in Enter-Query mode.

How Triggers Lack Intelligence

The following points demonstrate the abnormal behavior of triggers:

  • While overwriting the name , Forms still accepts a WHEN-VALIDATE-RECORD trigger at the item level. However, Forms does not show the same trigger when you create a trigger in the normal way by clicking the Create icon or dragging and dropping. This is how it allows you to define triggers at an inappropriate level.
  • At the form level, Forms allows you to define a WHEN-TAB-PAGE-CHANGED trigger even if there are no tabbed canvases in the form. The point to be noted here is that it should not allow you to write the said trigger until there is at least one tabbed canvas in the form.

GUI Development

Advanced GUI Development: Developing Beyond GUI

Multi-form Applications

Advanced Forms Programming

Error-Message Handling

Object-oriented Methods in Forms

Intelligence in Forms

Additional Interesting Techniques

Working with Trees

Oracle 8 and 8i Features in Forms Developer



Oracle Developer Forms Techniques
Oracle Developer Forms Techniques
ISBN: 0672318466
EAN: 2147483647
Year: 2005
Pages: 115

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